Flotillin1 promotes EMT of human small cell lung cancer via TGF-β signaling pathway

BUB1 induces AKT/mTOR pathway activity to promote EMT induction in human small cell lung cancer

Small cell lung cancer (SCLC) is a very aggressive tumor. Abnormal expression of BUB1 has been reported in several cancer types, wherein it plays a range of functional roles. This work aimed to elucidate the functional significance and molecular impacts of BUB1 in SCLC. It was found that SCLC cell lines exhibited significant BUB1 upregulation relative to control bronchial cells using data from the Gene Expression Omnibus (GEO) database and verified by immunohistochemical staining. BUB1 was also found to promote the proliferative, migratory, invasive activity of SCLC cells, as shown by CCK-8, 3D migration wound-healing, and Transwell assays, as well as flow cytometry. Additionally, it was found that BUB1 silencing enhanced E-cadherin expression while suppressing N-cadherin, Vimentin, ZEB-1, and Snail levels, as shown by Western immunoblotting. The loss of BUB1 also reduced p-AKT and p-mTOR levels without altering total AKT or mTOR protein levels. In conclusion, BUB1 functions as an oncogenic promoter in SCLC, potentially regulating the epithelial-mesenchymal transition by activation of AKT/mTOR signaling.

The roles of FLOT1 in human diseases (Review)

FLOT1, a scaffold protein of lipid rafts, is involved in several biological processes, including lipid raft protein‑-dependent or clathrin‑independent endocytosis, and the formation of hippocampal synapses, amongst others. Increasing evidence has shown that FLOT1 can function as both a cancer promoter and cancer suppressor dependent on the type of cancer. FLOT1 can affect the occurrence and development of several types of cancer by affecting epithelial‑mesenchymal transition, proliferation of cancer cells, and relevant signaling pathways, and is regulated by long intergenic non‑coding RNAs or microRNAs. In the nervous system, overexpression or abnormally low expression of FLOT1 may lead to the occurrence of neurological diseases, such as Alzheimer's disease, Parkinson's disease, major depressive disorder and other diseases. Additionally, it is also associated with dilated cardiomyopathy, pathogenic microbial infection, diabetes‑related diseases, and gynecological diseases, amongst other diseases. In the present review, the structure and localization of FLOT1, as well as the physiological processes it is involved in are reviewed, and then the upstream and downstream regulation of FLOT1 in human disease, particularly in different types of cancer and neurological diseases are discussed, with a focus on potentially targeting FLOT1 for the clinical treatment of several diseases.

FLOT1 knockdown inhibits growth of AML cells through triggering apoptosis and pyroptosis

Acute myeloid leukemia (AML) is a group of hematological malignancies characterized by clonal proliferation of immature myeloid cells. Lipid rafts are highly organized membrane subdomains enriched in cholesterol, sphingolipids, and gangliosides and play roles in regulating apoptosis through subcellular redistribution. Flotillin1 (FLOT1) is a component and also a marker of lipid rafts and had been reported to be involved in the progression of cancers and played important roles in cell death. However, the role of FLOT1 in AML remains to be explored. In this study, we found that increased expression of FLOT1 was correlated with poor clinical outcome in AML patients. Knockdown of FLOT1 in AML cells not only promoted cell death in vitro but also inhibited malignant cells engraftment in vivo. Mechanically, FLOT1 knockdown triggered apoptosis and pyroptosis. FLOT1 overexpression promoted AML cell growth and apoptosis resistance. Our findings indicate that FLOT1 is a prognostic factor of AML and may be a potential target for AML treatment.

GFPT1 promotes the proliferation of cervical cancer via regulating the ubiquitination and degradation of PTEN

Cervical cancer demonstrates the fourth incidence and death rate in females worldwide. Glutamine--fructose-6-phosphate transaminase 1 (GFPT1), the first rate-limited enzyme of the hexosamine biosynthesis pathway, has been reported to promote the progression of cancers. However, the prognostic value and roles of GFPT1 in cervical cancer are largely unknown. Transcription expression data for cervical cancer were downloaded from public databases. GFPT1 overexpressed and knockdown cell lines were constructed. Colony formation assays, Edu assays and 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays were used to measure the proliferation capabilities of cervical cancer cells. Western blot, Immunofluorescence and co-immunoprecipitation assays were performed to verify the interaction between GFPT1and Phosphatase and tensin homolog (PTEN). Animal assays were applied to verify the results in vivo. GFPT1 expression was higher in cervical cancer cell lines. The proliferation capabilities of cervical cancer cells were suppressed in GFPT1 knockdown cells and GFPT1 inhibitor L-DON treated cells. And overexpression of GFPT1 promoted cell proliferation. PTEN was up-regulated in GFPT1 knockdown cells and downregulated in GFPT1 overexpression cells. Immunofluorescence and co-immunoprecipitation results showed that GFPT1 was co-localized and interacted with PTEN. GFPT1 promoted the ubiquitination and degradation of PTEN. Silence of PTEN offsets the growth inhibition of cervical cancer caused by GFPT1 knockdown. Animal assays showed that GFPT1 promoted the proliferation of cervical cancer in vivo. Our study revealed that GFPT1 could promote the progression of cervical cancer by regulating PTEN expression. Our study highlights the GFPT1-PTEN regulation as a potential therapy target for cervical cancer. .

Modulation of macrophage inflammatory function through selective inhibition of the epigenetic reader protein SP140

Background

SP140 is a bromodomain-containing protein expressed predominantly in immune cells. Genetic polymorphisms and epigenetic modifications in the SP140 locus have been linked to Crohn’s disease (CD), suggesting a role in inflammation.

Results

We report the development of the first small molecule SP140 inhibitor (GSK761) and utilize this to elucidate SP140 function in macrophages. We show that SP140 is highly expressed in CD mucosal macrophages and in in vitro-generated inflammatory macrophages. SP140 inhibition through GSK761 reduced monocyte-to-inflammatory macrophage differentiation and lipopolysaccharide (LPS)-induced inflammatory activation, while inducing the generation of CD206⁺ regulatory macrophages that were shown to associate with a therapeutic response to anti-TNF in CD patients. SP140 preferentially occupies transcriptional start sites in inflammatory macrophages, with enrichment at gene loci encoding pro-inflammatory cytokines/chemokines and inflammatory pathways. GSK761 specifically reduces SP140 chromatin binding and thereby expression of SP140-regulated genes. GSK761 inhibits the expression of cytokines, including TNF, by CD14⁺ macrophages isolated from CD intestinal mucosa.

Conclusions

This study identifies SP140 as a druggable epigenetic therapeutic target for CD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-022-01380-6.

Flotillin-1 promotes EMT of gastric cancer via stabilizing Snail

Gastric cancer is one of the most common malignancies worldwide and has been identified as the third leading cause of cancer-related mortality. Flotillin-1 is a lipid raft-associated scaffolding protein and plays an important role in the progression and development of several malignant carcinomas. Flotillin-1 is involved in epithelial-mesenchymal transition (EMT) process of several solid tumors to promote metastasis. However, the detailed characteristics and mechanisms of Flotillin-1 in gastric cancer have rarely been investigated. In this study, we found Flotillin-1 upregulated in gastric cancer, and the high expression of Flotillin-1 correlated with a worse prognosis. The migration and invasion ability of gastric cancer cells was upregulated by overexpressing Flotillin-1. Knockdown of Flotillin-1 inhibits gastric cancer cells metastasis. Flotillin-1 is a key regulator of EMT process and promotes gastric cancer cells metastasis through inducing EMT. Flotillin-1 may interact with a deubiquitinase to inhibit the ubiquitination of Snail in gastric cancer cells to promote EMT process. Our study provides a rationale and potential target for the treatment of gastric cancer.

Piezo1 promoted hepatocellular carcinoma progression and EMT through activating TGF-β signaling by recruiting Rab5c

BACKGROUND

Piezo1 has been revealed to play a regulatory role in vascular development and progression of variety tumors. However, whether and how the progression of hepatocellular carcinoma (HCC) regulated by Piezo1 remains elusive. This study aimed to elucidate the effect and mechanisms of Piezo1 in HCC.

METHODS

The mRNA and protein expression level of Piezo1 in HCC samples and cell lines was determined by qRT-PCR, western blot and immunohistochemistry analyses. Two independent study cohorts containing 280 patients were analyzed to reveal the association between Piezo1 expression and clinicopathological characteristics. Series of in vitro and in vivo experiments were used to validate the function of Piezo1 in HCC. Gene set enrichment analysis (GSEA) was performed to explore the signaling pathway of Piezo1. Immunoprecipitation, immunofluorescence and in vitro and in vivo experiments were used to explore the molecular mechanism of Piezo1 in HCC progression.

RESULTS

Our results demonstrated the Piezo1 expression was significantly upregulated in HCC tissues and cell lines, and upregulation of Piezo1 closely correlated with aggressive clinicopathological features and poor prognosis. Knockdown of Piezo1 in HCCLM3 and Hep3B cells significantly restrained proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of HCC cells in vitro, and tumor growth, metastasis, EMT in vivo. TGF-β signaling pathway was most significant enriched pathway in GSEA. Finally, tumor promotion effect of Piezo1 was found to exerted through recruiting and combining Rab5c to activating TGF-β signaling pathway.

CONCLUSIONS

Piezo1 significantly related to poor prognosis and promotes progression of hepatocellular carcinoma via activating TGF-β signaling, which suggesting that Piezo1 may serve as a novel prognostic predictor and the potential therapeutic target for HCC patients.

MicroRNA (miR)-355 Suppressed Small Cell Lung Cancer Cell Metastasis via Regulating P38 Mitogen-Activated Protein Kinases (MAPKs) Signaling

MicroRNA (miR)-355 was reported to mediate p38 mitogen-activated protein kinases (MAPKs) signaling, which exerted an effect on cell invasion and metastasis. But whether miR-355 could inhibit small cell lung cancer cell line H446 cell metastasis by regulating p38 MAPKs signaling needs further study. H446 cells were cultured to establish miR-355 overexpression group and blank group. The expression of MT1-MMP, the activity and migration of H446 cells were evaluated. Further, the ability of invasion, the level of p-p38 MAPKs and the activity degree of MT1-MMP were observed in H446 cells. MT1-MMP was mainly expressed on the cell membrane. miR-355 overexpression significantly decreased cellular viability and reduced MT1-MMP and p-p38 MAPKs levels relative to the blank group without influencing p38 MAPKs level. In addition, miR-355 overexpression suppressed cell migration and invasive ability in H446 cells. Finally, miR-355 overexpression reduced pro-MMP and MMP-2 activity in H446 cells. miR-355 overexpression suppressed H446 cell metastasis through regulating P38 MAPKs signaling.

DCLK1-Short Splice Variant Promotes Esophageal Squamous Cell Carcinoma Progression via the MAPK/ERK/MMP2 Pathway

Cancer stem cell (CSC) marker doublecortin-like kinase 1 (DCLK1) contributes greatly to the malignancy of gastrointestinal cancers, and DCLK1-targeted agents have potential therapeutic value. However, the molecular pathways regulated by DCLK1-S (DCLK1 isoform 4), a shortened splice variant of DCLK1, still remain obscure. Here we found that the expression of DCLK1-S is significantly increased in human esophageal squamous cell carcinoma (ESCC) tissues and associated with malignant progression and poor prognosis. Functional studies indicated that silencing total of DCLK1 mediated by CRISPR/Cas9 inhibited ESCC cell proliferation, migration, and invasion. Conversely, these changes were largely reversed after DCLK1-S rescue or overexpression. More importantly, DCLK1-S significantly enhanced primary tumor formation and metastatic lung colonization in vivo. The Cancer Genome Atlas database and molecular analysis showed that DCLK1-S was closely related to the epithelial-mesenchymal transition (EMT) process in patients with ESCC. Further RNA sequencing and Kyoto Encyclopedia of Genes and Genomes analysis demonstrated that MAPK signaling pathway was significantly enriched. Our in vitro study proclaimed that DCLK1-S induced MMP2 expression in ESCC cells via MAPK/ERK signaling, leading to the activation of EMT. In addition, administration of ERK1/2 blocker SCH772984 attenuated the proliferative and migratory phenotype induced by DCLK1-S. In conclusion, these findings suggest that DCLK1-S may be a key molecule in MAPK/ERK/MMP2 pathway-mediated progression of ESCC, and that it has potential as a biomarker or therapeutic target to improve outcomes in patients with ESCC. IMPLICATIONS: : DCLK1-S induces ESCC progression by activating the MAPK/ERK/MMP2 axis and may serve as a prognostic biomarker or therapeutic target for patients with ESCC.

A mesenchymal-like subpopulation in non-neuroendocrine SCLC contributes to metastasis

Small cell lung cancer (SCLC) is the most aggressive lung cancer with high heterogeneity. Mouse SCLC cells derived from the Rb1L/L/Trp53L/L (RP) autochthonous mouse model grew as adhesion or suspension in cell culture, and the adhesion cells are defined as non-neuroendocrine (non-NE) SCLC cells. Here, we uncover the heterogenous subpopulations within the non-NE cells and referred to them as mesenchymal-like (Mes) and epithelial-like (Epi) SCLC cells. The Mes cells have increased capability to form colonies in soft agar and harbored stronger metastatic capability in vivo when compared with the Epi cells. Gene Set Enrichment Analysis reveals that the transforming growth factor (TGF)-β signaling is enriched in the Mes cells. Importantly, inhibition of the TGF-β signaling through ectopic expression of dominant-negative Tgfbr2 (Tgfbr2-DN) or treatment with Tgfbr1 inhibitor SD-208 consistently abrogates tumor metastasis in nude mouse allograft assays. Moreover, genetic deletion of Tgfbr2 or Smad4, the key components of the TGF-β signaling pathway, dramatically attenuates SCLC metastasis in the RP autochthonous mouse model. Collectively, our results uncover the high heterogeneity in non-NE SCLC cells and highlight an important role of TGF-β signaling in promoting SCLC metastasis.

Circ_001209 aggravates diabetic retinal vascular dysfunction through regulating miR-15b-5p/COL12A1

OBJECTIVE

Diabetic retinopathy, a common complication of diabetes mellitus and a major cause of blindness. circRNAs spongs target miRNA and thus influencing mRNA expression in DR. We investigated the mechanism of circ_001209 in regulating diabetic retinal vascular dysfunction.

METHODS

QRT-PCR analysis was performed to detect the expression of miR-15b-5p, COL12A1 and circ_001209 in human retinal vascular endothelial cells (HRVECs) under high glucose conditions. Western blot assay, wound healing assay, transwell assay and tube formation were used to explore the roles of circ_001209/miR-15b-5p/COL12A1 in retinal vascular dysfunction. Bioinformatics analysis and luciferase reporter, RNA-FISH, and overexpression assays were performed to reveal the mechanisms of the circ_001209/miR-15b-5p/COL12A1 interaction. TUNEL staining and H&E staining were used to evaluate the pathological changes in streptozotocin (STZ)-induced DR in rats.

RESULTS

Downregulation of miR-15b-5p under HG conditions promoted proliferation, migration, and tube formation of HRVECs. QRT-PCR and western blot results revealed that miR-15b-5p affected the HRVECs function through targeting COL12A1. Under HG conditions, circ_001209, which acts as a sponge of miR-15b-5p, is upregulated. Besides, overexpression of circ_001209 can affect HRVEC function and aggravate retinal injury in diabetic rats.

CONCLUSION

Upregulation of circ_001209 contributes to vascular dysfunction in diabetic retinas through regulating miR-15b-5p and COL12A1, providing a potential treatment strategy for diabetic retinopathy.

Overexpression of hsa_circ_0001445 reverses oxLDL‑induced inhibition of HUVEC proliferation via SRSF1

Atherosclerosis is a primary cause of multiple types of cardiovascular disease, including myocardial infarction. In addition, injury of human umbilical vein endothelial cells (HUVECs) can lead to the development of atherosclerosis. Circular (circ)RNAs participate in atherosclerosis. It has previously been shown that circRNA cSMARCA5 (hsa_circ_0001445) expression is downregulated in atherosclerosis. However, the effects of hsa_circ_0001445 on the proliferation of HUVECs remain unclear. In order to mimic atherosclerosis in vitro, HUVECs were treated with oxidized low-density lipoprotein (oxLDL). The expression levels of specific genes and proteins were detected in HUVECs by reverse transcription-quantitative PCR and western blot analysis, respectively. Cell proliferation was assessed by Cell Counting Kit-8 and 5-Ethynyl-2′-deoxyuridine staining. Cell apoptosis and 5,5′,6,6′-Tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine staining were examined by flow cytometry. In addition, the association between hsa_circ_0001445 and serine/arginine-rich splicing factor 1 (SRSF1) was investigated by RNA pull-down assay. hsa_circ_0001445 expression was downregulated in oxLDL-treated HUVECs. Moreover, oxLDL-induced inhibition of HUVEC proliferation was significantly reversed by overexpression of hsa_circ_0001445. oxLDL notably inhibited tube formation and mitochondrial membrane potential in HUVECs, while these effects were markedly reversed by hsa_circ_0001445 overexpression. Furthermore, overexpression of hsa_circ_0001445 reversed oxLDL-induced activation of β-catenin by binding to SRSF1. Collectively, these data demonstrated that overexpression of hsa_circ_0001445 reversed oxLDL-induced inhibition of HUVEC proliferation via activation of the SRSF1/β-catenin axis. These findings may provide novel targets for the treatment of atherosclerosis.

Decreased chromobox homologue 7 expression is associated with epithelial-mesenchymal transition and poor prognosis in cervical cancer

The aim of this study was to evaluate the association of the chromobox homologue 7 (CBX7) expression with the epithelial–mesenchymal transition in cervical cancer (CC), as well as with the disease prognosis. CBX7, E-cadherin (E-cad), and vimentin (VIM) expression levels were detected with immunohistochemistry. The relationship between the expression of CBX7, E-cad, and VIM expression and conventional clinicopathological characteristics of CC were evaluated. The positive expression rates of CBX7 and E-cad in the CC tissues were lower than the adjacent non-tumorous cervical tissues. Moreover, the VIM expression level was higher. The CBX7 expression was positively correlated with the E-cad expression, whereas was negatively correlated with the VIM expression. Furthermore, CBX7 was associated with the disease clinical staging, histological differentiation, lymph node metastasis, and vascular invasion. Patients with negative CBX7 expression showed decreased overall survival rates compared with those with low or high CBX7 expression. Multivariate Cox regression analysis indicated that the decreased CBX7 expression was an independent predictor for the poor prognosis of CC. In conclusion, the absence of CBX7 is associated with the histologic differentiation, lymphatic metastasis, vascular invasion, and poor prognosis of CC. CBX7 may be an independent prognostic factor for the prognosis of CC patients.

Rafting Down the Metastatic Cascade: The Role of Lipid Rafts in Cancer Metastasis, Cell Death, and Clinical Outcomes

Lipid rafts are tightly packed, cholesterol- and sphingolipid-enriched microdomains within the plasma membrane that play important roles in many pathophysiologic processes. Rafts have been strongly implicated as master regulators of signal transduction in cancer, where raft compartmentalization can promote transmembrane receptor oligomerization, shield proteins from enzymatic degradation, and act as scaffolds to enhance intracellular signaling cascades. Cancer cells have been found to exploit these mechanisms to initiate oncogenic signaling and promote tumor progression. This review highlights the roles of lipid rafts within the metastatic cascade, specifically within tumor angiogenesis, cell adhesion, migration, epithelial-to-mesenchymal transition, and transendothelial migration. In addition, the interplay between lipid rafts and different modes of cancer cell death, including necrosis, apoptosis, and anoikis, will be described. The clinical role of lipid raft-specific proteins, caveolin and flotillin, in assessing patient prognosis and evaluating metastatic potential of various cancers will be presented. Collectively, elucidation of the complex roles of lipid rafts and raft components within the metastatic cascade may be instrumental for therapeutic discovery to curb prometastatic processes.

Prognostic immunohistochemical markers for small cell lung cancer: A review

BACKGROUND

Small Cell Lung Cancer (SCLC) is one of the most aggressive thoracic malignancies and has been very challenging in developing personalized medicine. While immunohistochemistry (IHC) markers have established role in pathology diagnosis of SCLC, it is particularly important to apply early and simple methods to effectively determine the prognosis. This study aimed to review and identify prognostic protein markers that have potential to be incorporated into clinical care for SCLC.

METHODS

we systematically reviewed PubMed, Embase, Web of Science and Cochrane Library until October 19th, 2019 that reported prognostic IHC markers in SCLC. In this review, we focused on markers evaluated in at least two independent studies to compile the most forthcoming prognostic markers.

RESULTS

According to their function in the tumor, including proliferation-related markers, growth suppression-related markers, invasion- and metastasis-related markers, apoptosis-related markers, angiogenesis-related markers, immune regulation-related markers. Extensive reports into informative tables based on sufficiencies of evidence were summarized as some easy-to-use literature reservoirs for further referring.

CONCLUSIONS

Strong evidence supports that the 24 emerging markers or their combinations may be useful in predicting prognosis, helping personalized therapy decision-making for SCLC patients.

Serum MiR-4687-3p Has Potential for Diagnosis and Carcinogenesis in Non-small Cell Lung Cancer

The lack of a useful biomarker partly contributes to the increased mortality of non-small cell lung cancer (NSCLC). MiRNAs have become increasingly appreciated in diagnosis of NSCLC. In the present study, we used microarray to screen 2,549 miRNAs in serum samples from the training cohort (NSCLC, n = 10; the healthy, n = 10) to discover differentially expressed miRNAs (DEMs). Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) assay was applied to validate the expression level of selected overexpressed DEMs of NSCLC in a validation cohort (NSCLC, n = 30; the healthy, n = 30). Area under the receiver operating characteristic curve (AUC) was performed to evaluate diagnostic capability of the DEMs. The expression of the miRNAs in tissues was analyzed based on the TCGA database. Subsequently, the target genes of the miR-4687-3p were predicted by TargetScan. Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were tested by R software (ClusterProfiler package). NSCLC cells were transfected with inhibitor or mimic to down-regulate or up-regulate the miR-4687-3p level. The function of miR-4687-3p on proliferation, invasion, and migration of lung cancer cells were investigated through CCK-8 and Transwell assays, respectively. In the results, we identified serum miR-4687-3p that provided a high diagnostic accuracy of NSCLC (AUC = 0.679, 95%CI: 0.543-0.815) in the validation cohort. According to the TCGA database, we found that the miR-4687-3p level was significantly higher in NSCLC tissues than in normal lung tissues (p < 0.05). GO and KEGG pathway enrichment analysis showed that postsynaptic specialization and TGF-β signaling pathway were significantly enriched. Down-regulation of miR-4687-3p could suppress the proliferation, invasion, and migration of the NSCLC cells, compared with inhibitor negative control (NC). Meanwhile, overexpression of miR-4687-3p could promote the proliferation, invasion, and migration of the NSCLC cells compared with mimic NC. As a conclusion, our study first discovered that serum miR-4687-3p might have clinical potential as a non-invasive diagnostic biomarker for NSCLC and play an important role in the development of NSCLC.

NCBP3/SNHG6 inhibits GBX2 transcription in a histone modification manner to facilitate the malignant biological behaviour of glioma cells

RNA-binding proteins (RBPs) are significantly dysregulated in glioma. In this study, we demonstrated the upregulation of Nuclear cap-binding subunit 3 (NCBP3) in glioma tissues and cells. Further, knockdown of NCBP3 inhibited the malignant progression of glioma. NCBP3 directly bound to small nucleolar RNA host gene 6 (SNHG6) and stabilized SNHG6 expression. In contrast, the gastrulation brain homeobox 2 (GBX2) transcription factor was downregulated in glioma tissues and cells. SNHG6 inhibited GBX2 transcription by mediating the H3K27me3 modification induced by polycomb repressive complex 2 (PRC2). Moreover, GBX2 decreased the promoter activities and downregulated the expression of the flotillin protein family 1 (FLOT1) oncogene. In conclusion, NCBP3/SNHG6 inhibits GBX2 transcription in a PRC2-dependent manner to facilitate the malignant progression of gliomas.

Long Non-Coding RNA TUG1 Promotes Cell Proliferation and Inhibits Cell Apoptosis, Autophagy in Clear Cell Renal Cell Carcinoma via MiR-31-5p/FLOT1 Axis

Purpose

Clear cell renal cell carcinoma (ccRCC) is a common urological carcinoma in adults. Long non-coding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) has been reported to be involved in the progression of diverse human cancers, including renal cell carcinoma (RCC). However, the biological mechanism of TUG1 was rarely reported in ccRCC.

Methods

The levels of TUG1, microRNA miR-31-5p and flotillin 1 (FLOT1) in ccRCC tissues and cells were detected by qRT-PCR. The interactions between miR-31-5p and TUG1 or FLOT1 were predicted by starBase v2.0 and TargetScan, respectively, which were further validated by RIP assay and RNA pull-down assay. Cell counting kit-8 (CCK-8), flow cytometry and Western blot were used to assess the effects of TUG1 on cell viability, apoptosis rate and the relative protein expression levels in ccRCC cells. In addition, the xenograft tumor assay was conducted to further verify the functions of TUG1 in ccRCC in vivo.

Results

TUG1 was dramatically up-regulated in ccRCC tissues and cells. TUG1 silencing inhibited cell proliferation and promoted cell apoptosis, autophagy in 786-0 and A498 cells. In addition, TUG1 depletion repressed tumor growth in vivo. Moreover, miR-31-5p was validated as a direct target of TUG1, and microRNA miR-31-5p inhibitor mitigated the effects of TUG1 knockdown on ccRCC progression. Furthermore, FLOT1 was verified to be negatively interacted with miR-31-5p. FLOT1 overexpression attenuated miR-31-5p-mediated inhibitory effect on cell proliferation and promotion effects on cell apoptosis, autophagy. The restoration experiment implicated that TUG1 positively modulated FLOT1 expression by sponging miR-31-5p.

Conclusion

All data demonstrated that TUG1 promotes cell proliferation and inhibits cell apoptosis and autophagy in ccRCC by miR-31-5p/FLOT1 axis, which may provide a therapeutic target for ccRCC patients.

Suppression of miR-147b contributed to H37Rv-infected macrophage viability and migration in tuberculosis in vitro

BACKGROUND

Tuberculosis (TB) is a severe infectious disease. It was reported that microRNAs played important roles in tuberculosis. However, the role of miR-147b in the disease remained unveiling.

METHODS

Tuberculosis cell model was established using macrophage THP-1 cells infected with H37Rv strain. RT-qPCR was first for examination of miR-147b relative expression. Cell viabilities were then measured with MTT. Cell transfection was to interfere the relative expression of miR-147b or C11orf87 in infected cells. RT-qPCR was adopted to confirm the transfection efficiency. Luciferase assay verified the binding sites between miR-147b and C11orf87. Migration was examined by scratch and relative protein expression of EMT biomarkers and phosphorylation of Pi3K and AKT were assessed via Western blot.

RESULT

MiR-147b expression was higher and cell viability decreased in H32Rv-THP-1 cells. Cell viability was shown higher after miR-147b downregulation. Luciferase assay confirmed the binding. RT-qPCR found C11orf87 expression was lower in the H32Rv-THP-1 cells. MTT suggested that cell viability fell with the decrease of C11orf87 in infectious cells. Moreover, when H32Rv-THP-1 cells were co-transfected with miR-147b inhibitor and si-C11orf87, cell viability, migration and EMT and activation of Pi3K/AKT pathway was partially reversed compared with mere downregulation of miR-147b.

CONCLUSION

miR-147b might regulate macrophage proliferation and migration through targeting C11orf87 via Pi3K/AKT pathway in Tuberculosis in vitro, which calls for in-depth inter-cellular researches and animal researches to further support that miR-147b/C11orf87 axis might be a potential therapeutic target for the molecular treatment of Tuberculosis in the future.

Role of Focal Adhesion Kinase in Small-Cell Lung Cancer and Its Potential as a Therapeutic Target

Small-cell lung cancer (SCLC) represents 15% of all lung cancers and it is clinically the most aggressive type, being characterized by a tendency for early metastasis, with two-thirds of the patients diagnosed with an extensive stage (ES) disease and a five-year overall survival (OS) as low as 5%. There are still no effective targeted therapies in SCLC despite improved understanding of the molecular steps leading to SCLC development and progression these last years. After four decades, the only modest improvement in OS of patients suffering from ES-SCLC has recently been shown in a trial combining atezolizumab, an anti-PD-L1 immune checkpoint inhibitor, with carboplatin and etoposide, chemotherapy agents. This highlights the need to pursue research efforts in this field. Focal adhesion kinase (FAK) is a non-receptor protein tyrosine kinase that is overexpressed and activated in several cancers, including SCLC, and contributing to cancer progression and metastasis through its important role in cell proliferation, survival, adhesion, spreading, migration, and invasion. FAK also plays a role in tumor immune evasion, epithelial-mesenchymal transition, DNA damage repair, radioresistance, and regulation of cancer stem cells. FAK is of particular interest in SCLC, being known for its aggressiveness. The inhibition of FAK in SCLC cell lines demonstrated significative decrease in cell proliferation, invasion, and migration, and induced cell cycle arrest and apoptosis. In this review, we will focus on the role of FAK in cancer cells and their microenvironment, and its potential as a therapeutic target in SCLC.

Berberine inhibits epithelial-mesenchymal transition and promotes apoptosis of tumour-associated fibroblast-induced colonic epithelial cells through regulation of TGF-β signalling

Tumour-associated fibroblasts (TAFs) mediate the differentiation of adjacent stromal cells. Berberine (BBR), a monomer of traditional Chinese herbs, exhibits a potent therapeutic effect against cancer. However, the effects of BBR on the differentiation of normal colonic epithelial cells induced by TAFs have not been determined. In the present study, we selected the TAF-like myofibroblast cell line CCD-18Co. CCD-18Co-derived conditioned medium (CM) and co-culture induced epithelial-mesenchymal transition (EMT) changes in colonic epithelial HCoEpiC cells with decreased E-cadherin and increased vimentin and α-SMA expression. In addition, CCD-18Co stimulated the expression of ZEB1 and Snail and promoted motility. We used LY364947, a TGF-β receptor kinase type I (TβRI) inhibitor, and BBR. Our results showed that LY364947 and BBR inhibited these phenomena. BBR decreased the expression of ZEB1 and Snail, and this effect was concentration dependent. BBR also downregulated the expression of TβRI, TβRII, Smad2/p-Smad2 and Smad3/p-Smad3. In addition, BBR induced apoptosis in EMT-like HCoEpiC cells in a concentration-dependent manner with upregulation of Bax and downregulation of Bcl-2. However, VX-702, an inhibitor of p38 MAPK, significantly suppressed the apoptosis rate. BBR promoted the expression of p38 MAPK and phosphorylated p38 MAPK. In conclusion, berberine inhibits EMT and promotes apoptosis in TAF-induced colonic epithelial cells through mediation of the Smad-dependent and SMAD-independent TGF-β signalling pathways.